... and flange, polycarbonate window,brass or stainless steel internal and connection. Specifications are as follows:1) Dial size: 1.5, 2 ... , 3, 3.5, 4, 62) Connection size: 1/8, 1/4, 1/2, 3/83) Connection threads: npt, bsp, bspt 4) Material of the case ... , roll ring and flange: stainless steel5) Material of the connection and internal: brass, chrome ...